Scientists Reveal Spill of Toxic Ethanol Wastewater into the Philippines’ Largest Marine Protected Area for the Past 9 M

Marine scientists from Silliman University confirmed that Bais Bay continues to experience ecological degradation nine months after a containment lagoon operated by Universal Robina Corporation-Sugar and Renewables (URC-SURE) spilled massive amounts of ethanol waste into the Tañon Strait. Its latest assessment report shows recently killed corals accounted for up to 69% of the total coral cover in the assessed reef areas, a strong indication that the problem will persist unless the source of the spill is stopped. 

Field assessments conducted by Silliman University’s Institute of Environmental and Marine Sciences (IEMS) and Angelo King Center for Research and Environmental Management (SUAKCREM) and partners presented a consolidated report during an online forum co-organized by Oceana and Oceanus Conservation last week. The report establishes a causal link between the prolonged discharge of vinasse—a high organic load byproduct of ethanol production and the declining health of Bais Bay’s benthic habitats. 

Dr. Aileen Maypa, who led the ecological scientific team and is also a Pew Fellow in Marine Conservation, presented broadscale assessment habitat damage and water quality results with photo documentation of recently killed coral colonies and deteriorating seagrasses in North Bais Bay. The report detailed the ongoing process of eutrophication, which promotes algal blooms that subsequently compete with marine fauna for dissolved oxygen.  

Recent reported fish kills in the area also indicate ethanol waste discharge from the plant continues. “If the spill is not halted, the organic matter from the wastewater spill will continue to feed on the algal bloom. These algae and phytoplankton compete for the oxygen in the water that corals, seagrass and fish should be getting. That explains the deterioration and death of these marine habitats and the reported fish kill,” said Maypa. 

Maypa explained that the dark coloration and algal bloom also prevent photosynthetic organisms like seagrasses and corals from producing their food. She said ecosystem collapse could ensue, and the degradation may reach a threshold beyond which natural recovery becomes significantly protracted if not impossible. Restoration efforts will be futile unless the source of the spill is plugged now, according to her. 

Ricardo Aguilar, President of Fisherfolk Association of Manjuyod-Bais provided observations consistent with the scientific findings. He said fisherfolk continue to document effluent discharge via the plant’s drainage canals leading to the sea, despite prior assurances of cessation.   

“Pagkatapos ng October 2025, sabi nila, wala nang dumaan na waste. Pero nakita namin sa gilid ng highway, papunta sa may Taytay sa Alangilanan, doon sa canal, derecho sa sapa, derecho sa dagat. Palagi namang nag-leak ang lagoon nila. Mag high tide o low tide magpula ang tubig, derecho yan sa dagat,” he added. 

Maypa shared that she had confirmation from one of the biologists of Tañon Strait Protected Seascape (TSPS) who said another fishkill was reported in May. “If there was a fishkill again, then there must have been another spill,” she said.  

While red tide cells were detected at low densities, Dr. Maypa emphasized that the continued discharge from the plant warrants heightened surveillance of seafood safety in the affected waters. “Personally, I will be very cautious before I put something in my mouth, coming from Bais Bay,” Maypa added. 

Atty. Rose-Liza Eisma-Osorio, Oceana’s Senior Director for Campaigns and Policy said the local government and the Department of Environment and Natural Resources (DENR) have the obligation to stop the spill with urgency considering the emergency nature of its impact on the source of food and livelihood of the affected coastal communities.  

“The findings presented are not merely academic in nature; these constitute material evidence that is directly relevant to regulatory compliance, enforcement action, and the determination of legal responsibility. That is why we need to emphasize the precautionary principle and the polluter pays principle, both of which are firmly embedded in Philippine environmental policy,” added Osorio.  

Daisy Marie Gesim, representative of the Bais City LGU said they are coordinating with TSPS Management Body to enforce the closure of the lagoon of the ethanol plant. 

TSPS representative, Atty. Chad Ian Rubio said stopping the discharge of wastewater in Bais Bay requires the passage of the resolution from the Protected Area Management Board (PAMB) of TSPS. 

The DENR has confirmed that the containment lagoon that breached in October 2025 was constructed without the requisite permits and operational clearances. The facility has effectively operated outside its approved mandate, meaning that episodes of discharges were not accidents but a sustained non-compliance issue that has persisted without adequate regulatory intervention.  

Aguilar said the fisherfolk fear harvesting their seaweed because of the scale of destruction their farms suffered. “Kawawa naman ang mga mananagat kasi wala nang ikinabubuhay. Kung merong isda, hindi naman nabibili. Lagi kami ang nagtitiis. Ang mga anak ng mga mananagat, hindi na makaeskwela. Ang gobyerno, oo lang ng oo pero wala namang ginagawa. Ang mga pulitiko maganda lang pag malapit na ang eleksyon. Tulong kami pero pag andyan na, hindi na kami pinapansin,” Aguilar lamented.  

“Where scientific evidence demonstrates significant risk or actual harm, regulatory agencies are obligated to take timely and decisive action to prevent further degradation and begin full environmental restoration. We call on the national government and other concerned agencies to respond with urgency in ensuring that the Tañon Strait, the largest marine protected seascape in the country – is never again treated as a sacrifice zone,” said Von Hernandez, Oceana’s Vice President. (END) 

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